CNBP: A new member of the Wnt ancient pathway?

EZEQUIEL MARGARIT; NICOLAS GARCÍA SIBURU; PABLO ARMAS; NORA B CALCATERRA

Capital Federal

Congreso; 49th Annual Meeting Argentine Society for Biochemistry and Molecular Biology.; 2013

SAIB - Sociedad Argentina de Investigación en Bioquímica y Biología Molecular

CNBP is a nucleic acid chaperone highly conserved among vertebrates required for proper craniofacial development. The CNBP molecular targets identity is still limited. By using the MEME/MAST software, we searched for genes from human, mouse, chicken, amphibian and fish containing the recently determined DNA-binding site consensus in their promoters. Bioinformatic analyses retrieved 16 putative targets conserved among the five species, mainly comprising transcription factors, membrane receptors and signaling proteins. Gene ontology analysis retrieved terms related to development and general metabolism. Noteworthy, three of the identified genes (ptk7, tcf7l2, cdk14) are involved in the canonical Wnt pathway. CNBP binding to the promoters of these genes was validated by ChIP on DNA samples of 24-hpf zebrafish embryos. The role of CNBP on the expression of the target genes was assessed by knocking-down or overexpressing CNBP in 24-hpf zebrafish embryos. Data from RT-qPCR and whole mount in situ hybridization showed that CNBP enhances the expression of all the tested genes. A recent report shows that CNBP negatively controls the expression of wnt5b, a member of the non-canonical Ca2+-Wnt pathway. Collectively, our data suggest a role of CNBP in balancing the canonical and non-canonical Wnt pathway during embryonic development.